Technical Field
The present invention relates to polymer production. More particularly, the present invention relates to methods for producing high-density polyethylene (HDPE) nanocomposites.
Description of the Related Art
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.
The commercial success of polyethylene (PE) made it attractive for academic and industrial researchers to develop and improve its properties by proposing several techniques such as making new polyethylene-based composite. The selection of proper filler is very important to target the end usage [Zhang R X, Ni Q Q, Natsuki T, Iwamoto M (2007) Compos Strict 79: 90-96—incorporated herein by reference in its entirety]. The physiochemical characteristics of both the filler and the host polymer strongly control the final performance of the nanocomposites [Serkan T H, Dilek K (2007) J Reinforced Plastics and Composites 26: 113-121; Chow T S (1980) J Mate Sci 15:1873-1888—each incorporated herein by reference in its entirety]. In addition, the preparation method plays a significant role in shaping the final properties of the filled polymer. The small size of nano materials attracts researchers to use them as a replacement for the conventional fillers in the polymeric industry [Farzana H, Mehdi H, Masami O, Russel E, Gorga, (2006) Review article: Polymer-matrix Nanocomposites, Processing, Manufacturing, and Application: An Overview J Composite Materials September 1-65—incorporated herein by reference in its entirety]. The addition of those fillers during the polymerization as a drop in filler can affect the reaction mechanism and it can lead to higher active reaction [Mamdouh A H, Omar Y B, De S K, Reyad S (2013) U.S. Pat. No. 8,604,115; Mamdouh A H, Orner Y B, De S K, Reyad S (2013) U.S. Pat. No. 8,541,520; Hu Z, Liu C (2013) J Polym Res 20:39—each incorporated herein by reference in its entirety]. Different inorganic nanoparticles, such as titanium dioxide (TiO2), silicon dioxide (SiO2), aluminum trioxide (Al2O3) and zinc dioxide (ZrO2) have been used to improve and enhance the polymer properties [(René J N, Walter R C, Paul S (2003) Macromol Mater Eng 288:44-49; Wang Z, Li G, Xie G, Zhang Z (2005) Macrom Chem and Phys 206: 258-262; Xu D C, Zhi W, Zheng F L, Yu L M, Ming Q Z (2007) Polym Test 26: 202-208; Owpradit W, Jongsomjit B (2008) Mate Chem and Phys 112:954-961; Jongsomjit B, Chaichana E, Praserthdam P (2005) J Matr Sci 40: 2043-2045; Kontou E, Niaounakis M (2006) Polymer 47:1267-1280; Chaichana E, Jongsomjit B. Praserthdam P (2007) Chem Eng Sci 62: 899-905; Li K T, Dai C L, Kuo C W (2007) Catalysis Communications 81209; Kuoab M C, Tsaia C M, Huanga J C, Chena M (2005) Mate Chem and Phy 90:185-195; Desharun C, Jongsomjit B, Praserthdam P (2008) Cata Comm 9:522-528; Jongsomjit B. Panpranot J, Okada M, Shiono T, Praserthdam P (2006) Iranian. Polymer Journal (English Edition) 15:433-439; Jongsomjit B, Panpranot J, Praserthdam P (2007) Mat Let 61:1376-1379—each incorporated herein by reference in its entirety]. Moreover, these inorganic nanofillers can shape the morphology of the polymer during the reaction to produce bigger particles [Abdul Kaleel S H, Bahuleyan B K, De S K, Khan M J, Sougrat R, Al-Harthi M A (2012) J Ind and Eng Chem 18: 1836-1840; Bahuleyan B K, Atieh M A, De S K, Khan M J, Al-Harthi M A (2012) J Polym Res 19: 9744—each incorporated herein by reference in its entirety].
Ceramic materials have excellent thermal properties and they are being used to enhance the thermal stability of the polymer blends. This enhancement can be observed from the increase in the activation energy of degradation [Shi X, Wang J, Cai X (2013) International Polymer Processing 28: 228-235—incorporated herein by reference in its entirety]. In addition to the size and type of the filler, its shape plays a major role in the properties of the polymer composites. It is found that sphere like geometry of CaCO3 gives the high thermal stability while cubic CaCO3 has an adverse effect on the toughness [Kamil S, Fatih D, Mehmet B, Kaya I (2009) J Macromol Sci Part A 46:949-958—incorporated herein by reference in its entirety]. Similarly, statistical analysis showed that the grade of the same filler is a significant factor in determination of rheological properties of the polymer [Teixeira S C S, Moreira M M, Lima A P, Santos L S, De Rocha B M (2005) De Lima. Polym Test 24:983-987—incorporated herein by reference in its entirety]. Calcium zirconate (CaZrO3) is a ceramic material which has excellent thermal properties like high melting point of 2368° C.
The present disclosure provides methods for producing polyethylene where calcium zirconate is incorporated into the polymer as a filler.